Tag Archives: gut microbiota research

Recurrent Clostridium difficile associated diarrhea (rCDAD) Research Study Begins Enrollment

A research consortium across multiple institutions has begun enrolling patients in a clinical trial examining whether fecal microbiota transplantation by enema is safe and effective in preventing recurrent Clostridium difficile-associated disease, according to a press release.

The researchers hope to enroll 162 volunteers aged 18 years or older who have had two or more episodes of C. difficile-associated disease (CDAD) within the past 6 months, according to the release.

Trial sites include Emory University, Duke University Medical Center and Vanderbilt University Medical Center.

Each site is a member of the Vaccine and Treatment Evaluation Unit, which is a network funded by the National Institute of Allergy and Infectious Diseases (NIAID).

The researchers hope to enroll 162 volunteers aged 18 years or older who have had two or more episodes of C. difficile-associated disease (CDAD) within the past 6 months, according to the release.

Clostridium difficile-associated disease, a significant problem in health care facilities, causes an estimated 15,000 deaths in the United States each year,” Anthony S. Fauci, MD, NIAID director, said in the release. “This randomized, controlled trial aims to provide critical data on the efficacy and long-term safety of using fecal microbiota transplants by enema to cure C. diff infections.”

Volunteers will be enrolled in the trial after completing a standard course of antibiotics for a recurrent CDAD episode, presuming their diarrhea symptoms cease on treatment.

Participants will then be randomly assigned to either a group (n = 108) that will take an anti-diarrheal medication and receive a stool transplant (FMT) delivered by retention enema, or a group (n = 54) that will take an anti-diarrheal medication and receive a placebo solution delivered by retention enema.

The placebo is a saline solution that has been colored to mimic an active stool transplant product, to ensure that the study is partially blinded.

Researchers will collect stool and blood samples from participating at designated intervals for a year from the date of effective treatment for CDAD, or from the date of their last treatment if it was unsuccessful, according to the release.

Investigators will evaluate the stool samples for gut microbial diversity and infectious pathogens changes and will examine the blood samples for metabolic syndrome markers.

All participants will be monitored for adverse side effects for 3 years following the completion of recurrent CDAD treatment.

Source:  https://www.healio.com/gastroenterology/infection/news/online/%7B1402ede4-5de1-40a3-b23f-a0070e01ad7a%7D/trial-testing-fmt-for-recurrent-diarrheal-disease-begins

C.difficile Study Using C. difficile Conditioned Medium of Six Different C. difficile Strains

 

 

 

 

Abstract

Clostridium difficile infection (CDI) is typically associated with disturbed gut microbiota and changes related to decreased colonization resistance against C. difficile are well described.

However, nothing is known about possible effects of C. difficile on gut microbiota restoration during or after CDI.

In this study, we have mimicked such a situation by using C. difficile conditioned medium of six different C. difficile strains belonging to PCR ribotypes 027 and 014/020 for cultivation of fecal microbiota.

A marked decrease of microbial diversity was observed in conditioned medium of both tested ribotypes. The majority of differences occurred within the phylum Firmicutes, with a general decrease of gut commensals with putative protective functions (i.e. Lactobacillus, Clostridium_XIVa) and an increase in opportunistic pathogens (i.e. Enterococcus). Bacterial populations in conditioned medium differed between the two C. difficile ribotypes, 027 and 014/020 and are likely associated with nutrient availability. Fecal microbiota cultivated in medium conditioned by E. coli, Salmonella Enteritidis or Staphylococcus epidermidis grouped together and was clearly different from microbiota cultivated in C. difficile conditioned medium suggesting that C. difficile effects are specific.

Our results show that the changes observed in microbiota of CDI patients are partially directly influenced by C. difficile.

https://www.ncbi.nlm.nih.gov/pubmed/29180685?dopt=Abstract&utm_source=dlvr.it&utm_medium=twitter

Research Seeks Greater Insight Into Whether Changes In the Composition and Function Of the Gut Microbiota Are Associated With Disease

 

 

 

 

Health and Disease Imprinted in the Time Variability of the Human Microbiome

Abstract

The animal microbiota (including the human microbiota) plays an important role in keeping the physiological status of the host healthy.

Research seeks greater insight into whether changes in the composition and function of the microbiota are associated with disease.

We analyzed published 16S rRNA and shotgun metagenomic sequencing (SMS) data pertaining to the gut microbiotas of 99 subjects monitored over time.

Temporal fluctuations in the microbial composition revealed significant differences due to factors such as dietary changes, antibiotic intake, age, and disease.

This article shows that a fluctuation scaling law can describe the temporal changes in the gut microbiota. This law estimates the temporal variability of the microbial population and quantitatively characterizes the path toward disease via a noise-induced phase transition. Estimation of the systemic parameters may be of clinical utility in follow-up studies and have more general applications in fields where it is important to know whether a given community is stable or not. IMPORTANCE The human microbiota correlates closely with the health status of its host. This article analyzes the microbial composition of several subjects under different conditions over time spans that ranged from days to months. Using the Langevin equation as the basis of our mathematical framework to evaluate microbial temporal stability, we proved that stable microbiotas can be distinguished from unstable microbiotas. This initial step will help us to determine how temporal microbiota stability is related to a subject’s health status and to develop a more comprehensive framework that will provide greater insight into this complex system.

To review article/abstract please click on the following link:

https://www.ncbi.nlm.nih.gov/pubmed/28345059?dopt=Abstract&utm_source=dlvr.it&utm_medium=twitter